Former Crimewatch presenter Jacqui Hames has suggested that the News of the World placed her under surveillance because of the paper's links to suspects in a notorious murder case.
She rejected as "absolutely pathetic" ex-News of the World editor Rebekah Brooks's claim that the paper was investigating whether she was having an affair with detective chief superintendent Dave Cook, who was actually her husband.
Ms Hames, herself a former Scotland Yard detective, fought back tears as she told the Leveson Inquiry of the damaging effect that being followed by private investigators had on her and her marriage.
The News of the World placed the couple under surveillance after Mr Cook made an appeal on Crimewatch in June 2002 for information about the 1987 murder of private investigator Daniel Morgan, the inquiry into press standards heard.
Ms Hames alleged that Mr Morgan's firm Southern Investigations, whose members included suspects in the killing, had "close links" to senior News of the World news editor Alex Marunchak.
She said in a statement to the inquiry: "I believe that the real reason for the News of the World placing us under surveillance was that suspects in the Daniel Morgan murder inquiry were using their association with a powerful and well-resourced newspaper to try to intimidate us and so attempt to subvert the investigation.
"These events left me distressed, anxious and needing counselling, and contributed to the breakdown of my marriage to David in 2010. Given the impact of these events, I would like to know why the police did not investigate why we came to be placed under surveillance by a newspaper like this."
Earlier, the inquiry heard that police failed to tell Liberal Democrat deputy leader Simon Hughes that private investigator Glenn Mulcaire had his address, home phone number and personal details about his friends, the Leveson Inquiry has heard.
Scotland Yard detectives informed Mr Hughes in October 2006 that they had uncovered evidence Mulcaire had hacked his mobile phone while working for the News of the World.
The officers told him other politicians had also been targeted by the investigator but were not willing to go public and give evidence at a trial. But it was only in May last year that police showed Mr Hughes the extent of the information that Mulcaire held about him, the press standards inquiry heard.